The modifications to scroll compressors relate generally to scroll compressors, expanders, and vacuum pumps that alter or reduce the pressure of gases within a container. More specifically, these modifications refer to bellows design, liquid cooling of a compressor, and tip seal improvements.
A unique aspect of the present invention is two bellows that allow liquid cooling of the compressor.
Scroll devices have been used as compressors and vacuum pumps for many years. In general, they have been limited to a single stage of compression due to the complexity of two or more stages. In a single stage, a spiral involute or scroll upon a rotating plate orbits within a fixed spiral or scroll upon a stationery plate. A motor shaft turns a shaft that orbits a scroll eccentrically within a fixed scroll. The eccentric orbit forces a gas through and out of the fixed scroll thus creating a vacuum in a container in communication with the fixed scroll. An expander operates with the same principle only turning the scrolls in reverse. When referring to compressors, it is understood that expander or vacuum pump can be used.
Often oil is used during manufacture and operation of compressors. Oil free or oilless scroll type compressors and vacuum pumps have difficult and expensive manufacturing, due to the high precision of the scroll in each compressor and pump. For oil lubricated equipment, swing links often minimize the leakage from gaps in the scrolls by allowing the scrolls to contact the plate of the scroll. Such links cannot be used in an oil free piece of equipment because of the friction and wear upon the scrolls. If the fixed and orbiting scrolls in oil free equipment lack precision, leakage will occur and the equipment performance will decline as vacuums take longer to induce or do not arise at all.
Prior art designs have previously improved vacuum pumps, particularly the tips of the scrolls. In the preceding work of this inventor, U.S. Pat. No. 6,511,308, a sealant is applied to the scrolls during manufacturing. The pump with the sealant upon the scrolls is then operated which distributes the sealant between the scrolls. The pump is then disassembled to let the sealant cure. After curing the sealant, the pump is reassembled for use.
Then in U.S. Pat. No. 3,802,809 to Vulkliez, a pump, has a scroll orbiting within a fixed scroll. Beneath the fixed disk 13, a bellows 11 guides the gases evacuated from a container. The bellows spans between the involute and the housing, nearly the height of the pump. This pump and many others are cooled by ambient air in the vicinity of the pump.
The present art overcomes the limitations of the prior art where a need exists for bellows in liquid cooling of compressive equipment and improved tip seals upon spirals. That is, the art of the present invention, modifications to scroll compressors utilize two bellows between two scrolls for liquid cooling, an improved tip seal design, and an improved coating method of the spirals.